The present invention relates to a paper binding fastener and in particular to a paper binding fastener having two parts which can easily be disengaged and released.
It is known to bind paper sheets having holes punched therein by placing the sheets in a stack with their holes aligned and placing a binding device through the holes. Known binding devices include threaded fasteners with a male member and a female member inserted into the hole from opposite sides of the stack and rotated relative to each other to bind the sheets together. Such devices have the disadvantage that the threaded members must be rotated relative to each other a number of times for attachment and removal.
Other known devices are rivet-like members in which the male and female members rather than having threads, have ratchet-like catch teeth such that a catch carrying post extends into a catch socket for latching at different depths into the socket. Paper binding fasteners of this type are taught for example by U.S. Pat. No. 2,797,605 to Metze issued Jul. 2, 1957 and U.S. Pat. No. 3,251,260 to Serdechny issued May 17, 1966. Devices of this type suffer the disadvantage that there is no mechanism to release the two members.
Binding devices using rivet-like members with ratchet-like catch teeth are known which provide for release of the two members by use of a separate tool as taught for example by U.S. Pat. No. 2,583,224 to McDonald and U.S. Pat. No. 283,653 to Paxson. In Paxson, a pair of radially outwardly biased prongs may be drawn inwardly by a separate removable cylindrical key carrying a threaded forward socket. In McDonald, a pencil or other separate tool member is required to be urged to bind a pair of spaced arms apart for disengagement.
A disadvantage of devices as taught by Paxson and McDonald is that a separate tool is required and release of the paper binding fastener is not possible without the tool.
To at least partially overcome these disadvantages of previously known devices, the present invention provides a sheet binding fastener having two members which are secured together with ratchet-like catch teeth and which can be released by a component carried on one of the fastener members. The invention preferably provides a male member and a female member each having catch members which are moveable radially so as to engage and disengage the catch members and with at least one of the male and female members carrying an axially displaceable member which when axially moved as manipulated by a user urges the catch members radially to release the catch members from engagement and thus permit separation of the male and female members.
An object of the present invention is to provide an improved sheet binding device which can easily be disengaged and released.
Another object is to provide a paper binding device which permits ease of release of paper from a stack of paper.
Another object is to provide a paper binding device which can be made substantially entirely out of plastic as by injection molding.
Another object is to provide an inexpensive paper binding device which can be disengaged and released.
Accordingly, in one aspect, the present invention provides:
a paper binding fastener comprising:
a first member having an elongate cylindrical first tube open at a first end and having a flange extending radially outwardly from the first tube at a second end;
a second member having an elongate second tube open at a first end and having a flange extending radially outwardly from the second tube at a second end;
an interior diameter of the second tube being marginally less than an interior diameter of the first tube such that the first end of the second tube is insertable into the first end of the first tube for coaxial telescopic sliding of the second tube within the first tube;
the first member having a first catch member extending axially within the first tube towards the one end thereof and having a catch shoulder directed away from the one end;
the second member having a second catch member extending axially within the second tube towards the one end thereof and having a catch shoulder directed away from said one end;
on insertion of the second tube into the first tube, the catch shoulders of the first and second catch members moving axially past each other to assume positions with the catch shoulders opposed to each other whereby axially removal of the second tube from the first tube is prevented by engagement of the catch shoulders;
one of the first catch members and second catch members comprising a deflectable catch member being deflectable radially from an inherent position which it inherently assumes to a deflected release position in which the catch shoulders thereof is moved radially sufficiently to avoid engagement with the catch shoulder of the other catch member and permit axially movement of the second tube from the first tube;
the one of the first and second members carrying the deflectable catch member having a release member mounted thereto for axially sliding between an extended position and a retracted position;
a spring biasing the release member towards the extended position;
the release member on movement to the retracted position engaging the deflectable catch member and deflecting it to the release position;
the release member having an outer end adapted for engagement manually at the second end of the one of the first and second member carrying the deflectable catch member.
According to another aspect of the invention, there is provided a paper binding fastener comprising:
(a) an outer tubular member having a flange portion provided at a lower end thereof;
(b) an inner tubular member being disposed radially inwardly of said outer tubular member, said outer and inner tubular members being integrally connected at upper ends thereof forming a casing member having a central bore within said inner tubular member open at an upper end thereof and an annular space between said outer and inner tubular members open at a lower end thereof, said inner tubular member being provided with a plurality of openings disposed circumferentially about said inner tubular member;
(c) a female member having a base and a plurality of circumferentially spaced and upwardly extending arm members provided thereon each arm member having a plurality of catch members, said arm members being inserted into said annular space such that each catch member is adapted to be projecting radially and inwardly through an opening provided on said inner tubular member;
(d) a male member having a head portion, a central shaft portion and an annular skirt portion extending downwardly from said head portion, said shaft portion being provided with complementary catch members adapted to engage with corresponding catch members provided on said female member in an engaged position when said shaft portion is inserted into said central bore within said inner tubular member, whereas said annular skirt portion is adapted to slidably engage with said outer tubular member; and
(e) a resilient member being disposed between said flange portion of said outer tubular member and said base of said female member; whereby compression of said resilient member urges said upwardly extending arm members to yield radially outwardly into a disengaged position, thereby allowing said male member to be removed from said female member.
Three preferred embodiments of a sheet binding fastener of the present invention are disclosed, one of which having a generally symmetrical configuration, while the other two having an asymmetrical configuration. All three embodiments show a sheet binding fastener having a male member and a female member each having catch members for easy disengagement by simply compressing a resilient spring member in one single action. This renders the binding fastener of the present invention easy to release without any unscrewing or pinching action. The resilient spring member is preferably having adhesive material on both sides thereof so that it is adhered to and sandwiched between the casing member and the female element thereby forming a single female unit or member. Alternatively, the resilient spring member can be provided integrally on the casing member or the female element.
The sheet binding fastener may be used to bind various sheet materials including paper, paperboard, Mylar, textile, fabric and plastic sheets and the like. One preferred use is as a paper binding fastener.